Digital imaging devices and wireless communication technologies have seen dramatic improvements over the past years. Increasing number of today's mobile users carry multiple mobile devices. Various mobile devices such as Internet-enabled tablets, smart phones, and laptops have become essential personal accessories, connecting users to friends, work, and entertainment. These mobile devices have various features, can generate digital images, and can be used for different personal or professional purposes. Users now have more functionality choices and expect to use their mobile devices not only as communication tools but also as data and guidance systems.